Electrical apparatus for indicating and repeating movements at a distance



A J. L. ROUTIN ELECTRICAL APPARATUS FOR INDICATING AND REPEATING MOVEMENTS AT A DISTANCE Filed Feb. 25. 1920 2 Shaebs-Sheet' 1 Oct. 23, 1923. J. L. ROUTIN ELECTRICAL APPARATUS FOR INDICATING AND REPEATING MOVEMENTS AT A DISTANCE Filed Feb. 25, 1920 2 Sheets-Sheet 2 PatentedOct. 23, 1923.

2 UNITED- STATES.

v 1,471,708 PATENT OFFICE.

JOSEPH LOUIS BOUTIN, OI PARIS, rmcn ELECTRICAL APPARATUS FOR INDICATING AND BIPEA'I'IIG ID All A DISTANCE.

Application filed February 25, 1920. Serial Ho. 861,868.

To allwhom it may concern:

Be it known that I, JOSEPH LOUIS RoU'rIN, a citizen of the Republic of France, residing at Paris,- France, have invented new and '5 useful Im rovements in Electrical Apparatus for ndicating and Repeating Movements at a Distance, which invention is fully set forth-in the following specification.

The resent invention relates to improvements in electrical apparatus for indicating and repeating angular movements at a distance, and more particularly to apparatus of the above kind in which the princi le of the Wheatstone bridge is em loyed, w erein an annular rheostat is emp oyed at the transmitting station. and -is connected through a source of current to one 'or more like rheostats at the receiving stations, and has for its object to provide means to maintain the same difference of potential at the terminals of all the rheostats used as otentiometers.

When the distances separating the various stations do not exceed two or three hundred I metres, it is always easy to satisfy that confor the supply lines, a cross section sufiiciently large to always render any variaa result of temperature variations, negligible relatively'to the proper resistance of the rheostats. These ex dients are however inapplicable in practlce when the distances between the stations become greater.

The present invention consists of an improvement whereby messages can be transmitted correctly irres ctivel of the distance betweenthe stations, with the use of conductors of very small cross section only. This result is accomplished by a plying potential to the rheostat of eac receiving station adapted to be adjusted in such a manner as to be kept equal to the voltage which is supplied to' the rheostat at the transmitting station.

Fig. 1 of the accompanying drawings is a diagram illustrating the principle of the.

present invention.

Fig. 1' is a diagrammatic view showing a slight modification of the circuits shown in 2 is a diagrammatic View showing a or application of the principle of my invention. a a

Fig. l-shows two rheostats 1' and 2 situatdition by inserting adjustable resistances in j the circuits of the rheostats, and employing tions that may occur in their resistivities as ed respectively, the first one at the transm tting station and the second one at the re-' ceivlng station.

3 and 4 are two movable contacts.

5 and 6 are two conductors connecting .together the terminals of the rheostats 1 and 2. I

7 is a conductor connecting 3 to 4.

8 is a milliamperemeter inserted in the conductor 5 and situated at the receiving station.

9 is a voltmeter inserted in the conductor 7 and situated at the receiving station.

10 is a storage battery sltuated at the transmitting station, for supplying the rheostat 1.

11 is a storage battery situated at the receiving station for supplying a rheostat 12. I 13 is a movable contact on the rheostat 12; it allows of adjusting at will the supply of voltage to the rheostat 2.

14 1s a switch connected in series with the conductor 7.

In order to satisfy the condition as laid down above, that is to say, to supply the same voltage to the rheostats 1 and 2, it will be sufiicient, after having opened the circuit of conductor 7 by opening the switch 14, to

so operate the rheostat contact 13 as to bring the pointer of the milliam eremeter 8 to zero. Battery 10 a plies to t e terminals of rheostat 1 otentia s V, V. Battery 11, by aid of its r eostat, is adapted to lace on the terminals of rheostat 2 potentia s V", V'

equal to otentials V, V on conductors 5 and 6. hen this equality is established, no current flows in conductors 5 and 6. This condition is made known b milliam remeter 8 r'egisterin zero. e same driference of lpotential is thereby obtained at the termina s been done, the switch 14 is closed, and the orders are transmitted from 1 to 2, by the of both rheostats. When this has operator operating contact 4 in such a man-' ner as to keep thepointer of 9 at its'zero.

According to a, modification shown in Fig. 1', ommunication between the upper end of 12 and the battery 11 may be cut oil which is equivalent to connecting the adjustable rheostat 12 in series with 11 and 2 instead of connecting it in parallel with 11.

' Theexpedient to which recourse is bad teries as there are stations, and in regulating individually by means of auxiliary potentiometers (or of a rheostat connected in series), the potential with which eachre ceivin rheostat is supplied, so as to maintain the said voltage equal to that of the battery at the transmitting station.

It is obvious that the variations in the resistance of the supply lines 5 and 6 are necessary that the switch 11 shall be open during the time that the supply voltage of the rheostat 2 is being regulated because (assuming that 5 and 6 have equal resistances) when 14 is closed, 5 is traversed by half the current that can flow in 7 even in the case where the voltages at the terminals of l and 2 are absolutely equal to each other.

It should also be noted that once the equality of the voltages at the terminals of 1 and 2 has been attained, the circuit of conductor 5 can be opened by means of switch 14' without any inconvenience for using the apparatus for transmission at a distance, which is equivalent to making 3 and 4 agree with each other, because the conductor 6 is suflicient to assure the closing of the controlling current flowing in 7.

Fig. 2 illustrates the manner in which th improvement of the present invention can be applied to the case wherein the receiving station rheostats are connected only in a temporary manner to the contacts of the transmitter rheostat such as shown in the drawings of my Patent No. 1,409,586, issued March 14, 1922. The same letters of reference appearing in the said drawing are used to indicate the same parts in the present Fig. 2, wherein l designates the rheostat at the transmitting station and 33 the rheostats at the receiving stations, the lefthand end of rheostat 1 being permanently connected with the left-hand ends of rheostats 33 through line L. The right-hand end of rheostat 1 is successively connected with the right-hand ends of rheostats 33 through a distributor 16, the switch-arm 16' of which is rotated by means of a motor 24 through driving connections 27, 28. Rheostat 1 is provided with brushes 5, 7 revoluble on an axle 2. Brush 7 is connected through a milliamperemeter 26 with the switch-arm 23' of a distributor 23, and brush 5 is similarly connected to arm 22 of distributor 22 through a milliamperemeter 25. Arms 23, 22' are caused to rotate b motor 24 through drive connections 27, 29 and 30 respectively. Each distributor is rovided with a pair of contacts 31, 31' and 32, 32' wiped by arms 23', 22. Each receiving station is provided with a voltmeter 9, 9', each having a pair of coils 20, 21. One end of each coil has a connection terminating in a contact on one of the collectors 23, 22. The opposite ends of each pair of coils 20, 21 have connections with brushes 6, 8 0t rheostats 33. A storage battery 15, or other source of direct current, supplies the system with current. Potential is applied to the terminals of rheostats 3-3 by means of storage batteries 11 11, rheostat coils 12, 12, and sliding contacts 13, 13. Milliamperemeters 14 and 25 are inserted in the onductors connecting rheostats 3 to rheostat 1.

In order to establish the same difference of potential between the terminals of the left-hand rheostat 3, for example, as between the terminals of rheostat 1, the contact 13 is adjusted while arm 16' of distributor 16 passes over contact 16. By reason of the timing of contact arms 23 and 22' on distributors 23 and 22, the circuit through voltmeters 9, 9' 1s broken. Milliamperemeter 14 will give zero readin when the two differences of potential at rieostat 1 and rheostat 3 are the same as previously explained. In the same manner the difference of potential can be maintained in a permanent manner at the terminals of all therheostats, irrespective of the distances of the receiving stations from the transmitting station.

I claim:

1. Apparatus for indicating and controlling movements at a receiving station from a distant transmitting station comprising a Wheatstone bridge having one branch thereof located at the transmitting station and provided with means for applying potential thereto, the companion branch thereof being located at the receiving station and containing current detecting means, a bridge circuit between said transmitting station and said receiving station said circuit including a switch and a voltmeter and having sliding connections with its cooperating bridge branches, said receiving station branch being provided with means for applying a variable potential thereto when said switch is in 0 en position whereby the voltage at the receiving station is kept equal by a1d of said current detecting means to that at the sending station.

2. Apparatus for indicating and controlling movements at a receiving station from a distant transmitting station, comprising a plurality of rheostats one of which is located at a transmitting stat-ion and the other at a receiving station, a source of potential at y the transmitting station and conductors for connecting the same in parallel with said rheostats, one of said conductors including an amperemeter, a bridge circuit including a switch, a. voltmeter and sliding contacts movable over said rheostats, a separate source of potential at said receiving station and means for adjustably applying said potential across said receiving station rheostat when said first named switch is in open 0- sition whereby the voltage at the receivm station rheostat is kept equal by the aid 0% the amperemeter to that at the sending station rheostat.

3. Apparatus for indicating and controlling movements at receiving stations from a distant transmitting station comprising a plurality of rheostats one of which is located at the transmitting station and the others of which are located at the receiving stations, a source of potential atthe transmitting station, means adapted to connect:-

th same in parallel with said rheostats,

means including a separate source of. potential at each receiving station for regulating the difference of potential across the terminals of each of said receiving-station rheostats whereby the receiving-station voltages are kept equal that of the transmitting-station rheostat, bridge means for connecting said transmitting-station rheostat with each of said receiving-station rheostats, each of said means including a voltmeter and terminal sliding contacts, and current distributors for successively varying connections between said transmitting source of current and said bridge circuits and said receiving station rheostats.

In testimony whereof I have signed this specification.

' JOSEPH LOUIS ROUTIN. 

